Another slightly different active/stand-by question

I have been reading through all the posts about active/stand-by zimbra setups... looking to setup a warm redundancy server for our zimbra setup at a co-lo.

My thought... The store and index folders are all file based objects, right? Would it not be possible to rsync the index and store to a second server and either modify the mysql config for replication -or- use DRBD only for the DB and LDAP? This would suspect this could save a lot of wan traffic.

Anyone with more internal understanding know if this would work or if I am barking up the wrong tree?

Also, a side question for anyone with that kind of internal knowledge... forum searching didn't turn up any results, but can the index and store folders be placed on an NFS share?